Abstract: A module and an arrangement for, as well as a method of, generating a generally uniform distributed line pattern of light on a symbol to be read by image capture, include a light source for generating light along an optical axis in a distribution having different extents along intersecting directions generally perpendicular to the axis, and an optical component for receiving, and for optically modifying, the light from the light source to generate the generally uniform distributed line pattern of light on the symbol. The optical component includes a plurality of compound conic elements spaced apart from one another along one of the directions. Each compound conic element has a pair of conic segments for modifying the light along the one direction. A collimating lens modifies the light along the other of the directions. A solid-state imager has an array of image sensors for capturing return light from the symbol over a field of view having different extents along the intersecting directions.

Abstract: An imaging assembly in an imaging reader for electro-optically reading indicia includes a solid-state imager having an array of image sensors, and a focus control element, such as a liquid imaging lens, having a variable transfer function characteristics for capturing, optically modifying and directing return light from the indicia over a field of view onto the imager for processing into an electrical signal indicative of the indicia during a reading mode of operation; and a controller for controlling the imaging assembly to optically modify the return light in accordance with a known transfer function stored in a memory accessible to the controller during a calibration mode of operation prior to the reading mode.

Abstract: An imaging module is supported by a housing of a reader for electro-optically reading indicia. The imaging module includes a solid-state imager having an array of image sensors for capturing return light from the indicia during reading. A laser scanning module is also supported by the housing and includes a scanner for scanning at least one of a laser beam from a laser and a field of view of a light detector in a scan pattern across the indicia during reading. A controller is operatively connected to the modules, and is operative for preventing reading interference between the modules during reading.

Abstract: A method and apparatus for reducing speckle noise in laser based barcode readers. The apparatus includes a semiconductor laser diode for producing a laser beam. The apparatus also includes electronic circuitry operative to alternate the current passing through the semiconductor laser diode between a current above the threshold current and a current below the threshold current. The current passing through the semiconductor laser diode is alternated with a sufficiently high transition rate for reducing the coherence length of the laser beam.

Abstract: An imaging module is supported by a housing of a reader for electro-optically reading indicia. The imaging module includes a solid-state imager having an array of image sensors for capturing return light from the indicia during reading. A laser scanning module is also supported by the housing and includes a scanner for scanning at least one of a laser beam from a laser and a field of view of a light detector in a scan pattern across the indicia during reading. A controller is operatively connected to the modules, and is operative for preventing reading interference between the modules during reading.

Abstract: A module and an arrangement for, as well as a method of, generating a generally uniform distributed line pattern of light on a symbol to be read by image capture, include a light source for generating light along an optical axis in a distribution having different extents along intersecting directions generally perpendicular to the axis, and an optical component for receiving, and for optically modifying, the light from the light source to generate the gene rally uniform distributed line pattern of light on the symbol. The optical component includes a plurality of compound conic elements spaced apart from one another along one of the directions. Each compound conic element has a pair of conic segments for modifying the light along the one direction. A collimating lens modifies the light along the other of the directions. A solid-state imager has an array of image sensors for capturing return light from the symbol over a field of view having different extents along the intersecting directions.

Abstract: An imaging-based bar code reader including: an imaging system for imaging a target bar code within a field of view of the imaging system and projecting light from the field of view onto a sensor array, the imaging system generating image frames of the field of view of the imaging system; the imaging systems including an imaging lens assembly having a plurality of lens and a selection drive mechanism to select between a first optical zoom position defining a first focal length and a first field of view for imaging a target bar code at a close range and a second optical zoom position defining a second focal length and a second field of view for imaging a target bar code at a far range, the second focal length being greater than the first focal length.

Abstract: Electro-optical reading failure to read indicia due to specular reflection in the return light captured by a solid-state imager is prevented. An illuminator illuminates the indicia during reading with illumination light directed from an illuminating light source. In one embodiment, a controller is operative for detecting saturation in a captured image, and for reducing an intensity of the illumination light upon detection of the saturation. In another embodiment, the controller captures the return light in successive frames, and causes the illumination light to illuminate the indicia only during some of the frames. In yet another embodiment, the controller turns the illumination light on and off at a flash rate, and signals a user by changing the flash rate upon detection of the saturation to move a housing that supports the imager, illuminator and controller.

Abstract: Laser power control arrangements interrupt power to a laser used in electro-optical readers upon detection of operating conditions not conforming to preestablished standards, and adjust power to the laser to enhance reader performance without violating prevalent safety standards. Dual monitors are used to independently monitor the output power of the laser.

Abstract: An imaging-based bar code reader including: an imaging system for imaging a target bar code within a field of view of the imaging system and projecting light from the field of view onto a sensor array, the imaging system generating image frames of the field of view of the imaging system; the imaging systems including an imaging lens assembly having a plurality of lens and a selection drive mechanism to select between a first optical zoom position defining a first focal length and a first field of view for imaging a target bar code at a close range and a second optical zoom position defining a second focal length and a second field of view for imaging a target bar code at a far range, the second focal length being greater than the first focal length.

Abstract: An aiming light assembly of an imaging reader projects on a target, during an aiming mode of operation, an aiming light pattern that varies as a function of distance between a movable housing and the target. A solid-state imager captures light from the aiming light pattern during the aiming mode, and generates an electrical distance signal indicative of a target distance between the housing and the target. The imager also captures return light over a field of view from the target during a reading mode of operation after the aiming mode, and generates an electrical target signal indicative of the target. A controller processes the electrical distance signal during the aiming mode into data indicative of the target distance, and also processes the electrical target signal during the reading mode into data indicative of the target located at the target distance.

Abstract: The disclosed bar code reader includes an auto-focusing component for rapidly producing in focus images. An imaging system makes use of an aiming pattern that impinges upon the coded indicia of a target. The imaging system includes a light monitoring pixel array and a focusing lens that is fixed with respect to the pixel array for transmitting an image of the target object onto the pixel array. The imaging system also includes a movable mirror mounted for movement along a path of travel to reflect light passing through the focusing lens onto the pixel array. A drive motor moves the mirror relative the lens to adjust a focus of an image of the object formed at the pixel array. An automatic focusing component of the imaging system analyzes the aiming pattern reflected from the target object and projected onto the pixel array by the lens.

Abstract: A reader for, and a method of, electro-optically reading a symbol in a range of working distances include a housing, a data capture assembly supported by the housing for directing light at a variable power level at the symbol in a plurality of successive scans, and for detecting return light from the symbol, and a controller for controlling the data capture assembly by increasing the power level of the light during at least one of the successive scans to enable detection of the symbol located at an increased working distance from the reader, and by decreasing the power level of the light during at least another of the successive scans to maintain an output power level within safety limits. Preferably, the increased power level alternates with the decreased power level during successive scans.

Abstract: An image capture system for, and a method of, reading an optical code during a reading mode, comprise an aiming assembly including a laser for emitting a laser beam having a variable intensity, and for generating an aiming pattern from the laser beam during an aiming mode prior to the reading mode, and an imager for detecting and capturing an image of the aiming pattern and the code over a field of view by exposure over an exposure time period during the aiming mode, and for detecting and capturing an image of the code over the field of view during the reading mode. A controller is operative for controlling the intensity of the laser beam during the aiming mode by increasing the intensity of the laser beam during the exposure time period to enhance detection and capture of the aiming pattern by the imager, and by decreasing the intensity of the laser beam frame outside the exposure time period for user safety.

Abstract: Laser power control arrangements interrupt power to a laser used in electro-optical readers upon detection of an over-power condition not conforming to preestablished regulatory standards. In one embodiment, during an operational mode, a difference between laser drive currents at two operating points is compared to a difference between laser drive currents at the same two operating points during a calibration mode. The over-power condition is recognized when the difference during the operational mode exceeds the difference during the calibration mode by a predetermined amount. In another embodiment, the laser is only energized to emit the beam at a reduced power level well below regulatory standards for staring at even if a motor drive failed.

Abstract: A method and apparatus for improving the image quality obtained by an imaging-based scanner comprising a housing supporting one or more protective windows. The apparatus further comprises at least one scanning arrangement, the scanning arrangement comprising illumination and imaging optics. The illumination and imaging optics form a respective field of view for imaging a target object. A light baffle is attached to the scanning arrangement. The light baffle has an aperture corresponding to each of the illumination and imaging optics such that stray light reflected from the protective windows is absorbed by the light baffle, improving the image quality of the imaging-based scanner.

Abstract: Laser power control arrangements interrupt power to a laser used in electro-optical readers upon detection of an over-power condition not conforming to preestablished regulatory standards. In one embodiment, during an operational mode, a difference between laser drive currents at two operating points is compared to a difference between laser drive currents at the same two operating points during a calibration mode. The over-power condition is recognized when the difference during the operational mode exceeds the difference during the calibration mode by a predetermined amount. In another embodiment, the laser is only energized to emit the beam at a reduced power level well below regulatory standards for staring at even if a motor drive failed.

Abstract: An imaging assembly in an imaging reader for electro-optically reading indicia includes a solid-state imager having an array of image sensors, and a focus control element, such as a liquid imaging lens, having a variable transfer function characteristics for capturing, optically modifying and directing return light from the indicia over a field of view onto the imager for processing into an electrical signal indicative of the indicia during a reading mode of operation; and a controller for controlling the imaging assembly to optically modify the return light in accordance with a known transfer function stored in a memory accessible to the controller during a calibration mode of operation prior to the reading mode.

Abstract: An imaging lens assembly focuses light from indicia in a working range of distances along an optical path onto a solid-state imager of an imaging reader. The lens assembly includes a negative spherical aberration component and an aperture stop that together are operative for extending the working range.

Abstract: A system having a light source generating a light beam, a collimating lens collimating the light beam into a collimated light beam and a pattern generating element comprising a diffractive optical element portion and a refractive optical element portion, the pattern generating element creating a target pattern from the collimated light beam incident on the pattern generating element.